The levinson keyboard available here: https://keeb.io/products/nyquist-keyboard-pre-built 

Great alternative to the preonic. I made this case using OpenSCAD and then imported into FreeCAD to do filets. 

You can find the magnets on Amazon here: https://www.amazon.com/Niuknow-Neodymium-10x5x2mm-Double-Sided-Adhesive/dp/B0BTSWZSVG

You just need a 10x5x2 magnet. I have a two color version I did as well. 

Important Slicing Notes: On the MINI, use gyroid infill and don't use speed setting. Clean your nozzle. Works in PETG and PLA but the GCODE is for PETG